ABSTRACT
Objective To observe dexmedetomidine coordinate with mlelatonin attenuate the scopolamine-induced delirium in rats and its mechanism.Methods Thirty male adult SD rats aged 6-8 weeks were randomly divided into six groups:normal saline control group (group C),scopolamine-induced delirious model group (group S),dexmedetomidine group (group D),mlelaton group (group M),α-bungarotoxin antagonism group (group BM),joint protection group (group DM).A model of delirium was reproduced by intraperitoneal inj ection of scopolamine 1.8 mg/kg.The rats in group C was given equal sterile normal saline instead,the rats in group D was intraperitoneal injected of dexmedetomidine 40 μg/kg 15 minutes before scopolamine injection,the rats in group M was intrap-eritoneal injected of mlelaton 5 mg/kg in the contralateral abdominal at the same time with scopolamine injection,the rats in group BM was intraperitoneal injected ofα-BGT 1 μg/kg 15 minutes before scopolamine injection and mlelaton 5 mg/kg in the contralateral abdominal at the same time with scopolamine injection,the rats in group DM was intraperitoneal injected of dexmedetomidine 40 μg/kg 15 minutes before scopolamine injection and mlelaton 5 mg/kg in the contralateral abdominal at the same time with scopolamine injection.The rats were assigned for open field test 15 minutes before and 10 minutes after model reproduction for 15 minutes.The level ofα7nAchR in serum was deter-mined by enzyme linked immunosorbent assay.Results When compared with group C,rats in group S ran significant longer total distance and space distance,had faster total speed and space speed (P<0.05).When compared with group S,rats in group D,group M,group DM ran significant shorter total distance and space distance,had significant slower total speed and space speed (P<0.01 );when compared with group D,rats in group DM ran significant shorter total distance and space dis- tance (P<0.05 ),had slower total speed and space speed,however without significant statistical difference.When compared with that in group C,the level of α7nAChR in serum were significantly decreased in group S (P<0.05).When compared with group S,the level of α7nAChR were signifi-cantly increased in group D (P<0.01).There were no significant difference between group M and group S (P=0.96).When compared with group D,the level of α7nAChR had an elevated trend in group DM.Conclusion Dexmedetomidine can improve the symptoms of delirium,possibly by in-creasing the activity of alpha 7nAChR.Melatonin may improve the effect of dextromidine on delirium.
ABSTRACT
Four constitunets were isolated from the flower of Rhododendron molle ( BI. ) G. Don. One of these was named Rdl.The acute LD50 of Rdl in mice ( iv ) was found to be 4742 ug/kg.The hypotensive effect of Rdl was studied in various anesthesized animals. In cats, the dosage of 100, 300 and 500 Hg/kg of the Rdl ( iv ) reduced the blood pressure by 10:9% ( P